Judge it on merit, if the owner hadn’t mentioned the taxiness you’d not know. I’d be paranoid when checking it but I wouldn’t automatically walk away, if it’s outright shagged it’ll be impossible to hide it completely. My uncle was a minicab driver for a while, I’d snap up one of his old cars- daytime hires twice a week, and beautifully kept inbetween.
Or, I’ll sell you a Mondeo for £1500 and a week’s holiday, and deliver it at the start of the season. To save on the mileage and wear and tear, I’ll deliver it on a breakdown truck.
(that’s only half a joke- if cars are so expensive there, maybe a regular would be up for driving one down? )